Paper making and fiber liberation – Processes of chemical liberation – recovery or purification... – Waste paper or textile waste
Patent
1992-02-18
1994-04-12
Hastings, Karen M.
Paper making and fiber liberation
Processes of chemical liberation, recovery or purification...
Waste paper or textile waste
162 8, 162 65, D21F 502
Patent
active
053022440
ABSTRACT:
Waste cellulosic paper products, for example, old corrugated containers are recycled employing oxygen delignification in the presence of an alkaline material to produce a recycled pulp of lower kappa number, while maintaining adequate strength in the pulp. The recycling process preferably employs an acid pretreatment in combination with the oxygen delignification, and exposure of the waste product to the alkaline material is preferably controlled so that at any point in the delignification the waste product is exposed to not more than 50%, by dry weight, of the alkaline material based on the weight of residual lignin in the waste paper product.
REFERENCES:
patent: 4259150 (1981-03-01), Prough
patent: 4435249 (1984-03-01), Markham et al.
patent: 4436586 (1984-03-01), Elmore
patent: 4737238 (1988-04-01), de Ruvo
patent: 4897156 (1990-01-01), Samuelson
patent: 4946556 (1990-08-01), Prough
patent: 5211809 (1993-05-01), Naddeo et al.
"The Bleaching of Pulp" Tappi Press, 1979, p. 44.
Angulo "Enviromentally Safe Bleaching of Post Consumer Waste Papers" TAPPI Pulping Conf. Oct. 1990.
TAPPI Journal, 1986, "Upgrading of pulp from Corrugated containers by oxygen delignification," de Ruvo et al.
TAPPI Journal, 1988, "Oxygen bleaching of secondary fiber grades" Markham et al.
Domtar Inc.
Hastings Karen M.
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